The invention relates to a process for purifying a feed stream to a hydroformylation process.
A commonly practiced hydroformylation process reacts an olefin with CO and hydrogen to make an aldehyde. Commercial olefin feedstocks can contain unsaturated impurities such as methylacetylene (propyne) and propadiene, commonly referred to as MAPP gas, and 1,3-butadiene. These impurities can strongly bind to the hydroformylation catalyst as a poison/inhibitor. To remove these impurities, the liquid feedstocks can be sent through clean-up beds (referred to as MAPP beds) designed to react out small levels of polyunsaturated contaminants using a selective hydrogenation catalyst. If the concentration of 1,3-butadiene is too high, conventional MAPP bed operation is insufficient to reduce the concentration below levels that will be detrimental to hydroformylation activity while at the same time protecting the linear (1-butene) present in the feedstock.
It would be desirable to have an improved process for reducing the amount of unsaturated hydrocarbon impurities from hydroformylation feedstocks.